I bought this microphone for my work as a professional fitness instructor in a mid-size gym and there is absolutely nothing I can complain about.
The microphone fits perfectly to my head, and with some small adjustments, also to all my colleagues' heads. Four of us are actually using this mic on an everyday base for about a year now, and we all agree that this one is a very good replacement for the original AKG, we had before. Not to mention our boss, who is happy about the price. ;-)
We had a headset mic in the style of the t.bone 500 also, but we returned it, because of its bad fit.
Coming to audio quality, I don't feel myself able to judge this mic, because audio quality isn't what I'm looking for. In fact, a megaphone would also be ok, if it wouldn't be so unhandy. ;-)
Finally, I am very happy with my microphone and definitely recommend it to everybody, who is in a similar job or position as me.